I've been working on this on and off for the past few years.
ACE is an Amstrad/Schneider CPC emulator. The CPC is an 8-bit computer from the 80s (and early 90s). ACE is an emulator for it, originally written by OffseT for MorphOS. I porteed the code to Haiku, complete with native GUI.
The emulator has lot of nice features, including a disassembler, memory explorer/editor, etc. It is also one of the most accurate emulators available for the machine and does not need a very powerful computer to run.
Download the Haiku version here (32bit only):
It is recommended to install BeBrexx and iff_translator_x86 (both available from HaikuDepot) to fully enjoy ACE.